In a race of 1000 meters, A beats B by 200 meters and A beats C by 500 meters. Assuming that the contestants run at constant speeds, by how many meters does B beat C?
(A) 300 (B) 375 (C) 450 (D) 500 (E) 625
B speed =
C speed =
After t, B has 200 metres to travel, an extra quarter of his distance already travelled in t (not a fifth of 1000, it's a quarter of 800).
This will take him an extra
In , C will have travelled a quarter of 500,
which is 125 metres.
Therefore C still has 1000-(500-125) metres to travel, when B crosses the line.
Another approach (very primitive) . . .
In a 1000-m race, beats by 200 meters and beats by 500 meters.
Assuming that the contestants run at constant speeds, by how many meters does beat ?
The race ended like this:Code:C B A + - - - - - - - - - o - - - - - o - - - o 0 500 800 1000
ran 500 m in the time that ran 800 m.
C's speed is of 's speed.
When ran his last 200 m, ran only: . m.
As crosses the finish line, is at the 625-m mark.
Therefore, beats be 375 m . . . answer (B).